Nanowire Solar Cells Soak Up Sunlight (5 of 6) (image) American Association for the Advancement of Science Share Print E-Mail Caption This is a top-down SEM image of indium phosphide (InP) nanowires after growth. The nanowires are about 1.5 microns long and 0.18 microns in diameter, with a center to center distance of 0.47 microns (1 micron (µm) is equal to 1/1000 of a millimeter, that is, one millionth of a meter). This can be compared with the sunlight, which has most of its energy in a wavelength range from 0.5 to a few microns. The nanowires cover 12% of the surface as seen from top, that is, from the sun's point of view. On top of the nanowire is the gold particle which is used as a seed for the crystal growth. This image relates to a paper that appeared in Jan. 17, 2013, issue of Science Express, published by AAAS. The paper, by Jesper Wallentin at Lund University in Lund, Sweden, and colleagues was titled, "InP Nanowire Array Solar Cells Achieving 13.8% Efficiency by Exceeding the Ray Optics Limit." Credit [Image courtesy of Wallentin et al.] Usage Restrictions Please cite the owner of the image when publishing. This image may be freely used by reporters as part of news coverage, with proper attribution. Non-reporters must contact Science for permission. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.